BP 2025 (Ph. Eur. 11.6 update)
Action and use
Osmotic laxative; used in treatment of electrolyte deficiency.
Preparations
Magnesium Sulfate Injection
Magnesium Sulfate Mixture
Magnesium Sulfate, Potassium Chloride and Sodium Chloride Infusion
Ph Eur
DEFINITION
Content
99.0 per cent to 100.5 per cent (dried substance).
CHARACTERS
Appearance
White or almost white, crystalline powder or brilliant, colourless crystals.
Solubility
Freely soluble in water, very soluble in boiling water, practically insoluble in ethanol (96 per cent).
IDENTIFICATION
- It gives the reactions of sulfates (3.1).
- It gives the reaction of magnesium (3.1).
TESTS
Solution S
Dissolve 5.0 g in water R and dilute to 50 mL with the same solvent.
Appearance of solution
Solution S is clear (2.2.1) and colourless (2.2.2, Method II).
Acidity or alkalinity
To 10 mL of solution S add 0.05 mL of phenol red solution R. Not more than 0.2 mL of 0.01 M hydrochloric acid or 0.01 M sodium hydroxide is required to change the colour of the indicator.
Chlorides (2.4.4)
Maximum 300 ppm.
Dilute 1.7 mL of solution S to 15 mL with water R.
Iron (2.4.9)
Maximum 20 ppm.
Dilute 5 mL of solution S to 10 mL with water R.
Loss on drying (2.2.32)
48.0 per cent to 52.0 per cent, determined on 0.500 g by drying in an oven at 110-120 °C for 1 h and then at 400 °C to constant mass.
ASSAY
Dissolve 0.450 g in 100 mL of water R and carry out the complexometric titration of magnesium (2.5.11).
1 mL of 0.1 M sodium edetate is equivalent to 12.04 mg of MgSO4.
Ph Eur
